Let me clarrify, a pile of crap that has congealed into living creature. Think a frankenstein styled character that uses worms, rats (living and dead), body parts, slimy stuff, etc. The body movements similar to this guy http://www.youtube.com/watch?v=ioFAa2Q3B1k

Of course I realized he is a contortionist, but I just wanted to get across the boneless aspect of the character movement.

Make a Ghillie Suit using "trash", this way the actor can blend in in the room and really give a good startle, and you can cover his face and go for the sentient garbage pile thing or even make up his face to blend the trash pile/hobo thing.